Mycoplasma hyosynoviae Arthritis of Swine

Abstract

SUMMARY Arthritis caused by Mycoplasma hyosynoviae in 40- to 100-kg. swine is characterized by sudden onset of acute lameness. Gross lesions consist of increased serofibrinous to serosanguineous synovial fluid and swelling, discoloration, and hyperemia of the synovium in large diarthrodial joints. The joint capsules and articular surfaces usually are not affected. Mycoplasma hyosynoviae can be isolated from the synovial fluid, lymph nodes, and mucous membrane secretions of animals with the acute form of the disease. The organism persists indefinitely in the nasopharyngeal secretions and tonsils of convalescent and adult swine. Treatment with tylosin or lincomycin is most effective if these drugs are administered parenterally during the early stages of the disease. Control measures are not well established, but maintenance of closed herds may prevent introduction of the organism, and minimizing stress during the susceptible age period may help reduce the incidence of the disease.